Orthographic projections in Google Earth (/Sky) possible? Alternatives?

I need to create whole-sky maps, but Google Earth in Sky mode has limited "zoom out." Is it possible to create an orthographic map projection with Google Earth (or, for that matter, MS Virtual Earth)? Really any of the standard projections will do, although it would be nice to have options.

Of course, I could render the projection statically and then paint my KML layer on top of开发者_开发技巧 it, but the ideal use-case would allow the user to add additional KML layers, zoom in and out, etc.

No they don't. This was a bone of contention in a series of articles I wrote just over a year ago. I wasn't after an orthographic projection, but equal area projections. People insist on plotting geostatistical data on non-equal area projections, mainly because they don't know any better and/or Google Maps, Bing Maps, etc do not offer any alternatives.

my demo of how it should be done used OpenLayers which can support various different map projections.

I haven't seen OpenLayers being used for star maps, but I can't see any fundamental reasons why it should not work. Also the star data is generally available in the public domain, I believe.